Ink



Patented Aug. 26,1924.

UNITED STATES PATENT OFFICE.

ENRIQUE REITZE LN D EMILIO TRUJELO, OF SANTIAGO, CHILE.

INK.

Ho Drawing.

ing the authenticity of documents by the impression thereon of finger prints-as per our separate patent application, Serial No. 641,275, filed May as, 1923.

Th main feature of this special ink consists in the fact that it does not stain the fingers, sothat after settingthe print a damp sponge or cloth will eradicate all traces thereof from the finger.

The composition and manufacture of this ink is as follows:

Ten kilos of pure glycerin are heated in a bafio-maria, one kilo of gelatine is dissolved therein, and this mass then allowed to cool down to 20 C. Five kilos of alcohol are then added and all this is well stirred up to obtain the complete dissolution of all ingredients. This mass is mixed with two kilos of coloring matter in form of an impalpable powder, preferably blue-colored,

and then ground by means of a cylinder mill in order to make it uniform.

One may vary the intensity of the color,

Application filed May 24,

1923. Serial No. 641,276.

varying the roportion of the coloring matter employe the consistency may also be varied, increasing or decreasing the proportion of any of the other ingredients, especially of the gelatine.

This ink can be applied to stamp pads or used in any other desirable form. A handy portable form is a pocket stamp pad enclosed in a convenient shaped case and provided witha sponge for cleaning purposes.

Having thus described our invention, what we claim is:

ink formed of a mixture of gycerin, gelatine, alcohol and a coloring matter in the proportions by weight. of ten, one, five and two respectively.

2. The process of making ink which consists in heating ten parts by weight of glycerin' and dissolving therein one part by weight of gelatine, permitting the mixture to cool down to approximately 20 C., adding alcohol to the cooled mixture in the proportion by weight of one-half to one of glycerin, stirring said mixture, adding coloring matterto the mixture in the proportion by weight of one-fifth to one of glycerin, and grinding the mass.

In testimony whereof we have signed our names to this specification.

E-NRIQUE REITZE. EMILIO TRUJILLO.

. 1. An article of manufactur comprising 

